IFM Electronic CR0451 - Basic information about colours and bitmap graphics

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ifm System Manual ecomatmobile BasicDisplay (CR0451) V01
Visualisations in the device Basic information about colours and bitmap graphics
7.2 Basic information about colours and bitmap
graphics
Image size vector graphics / pixel graphics .................................................................................61
Colour for bitmap graphics ...........................................................................................................62
What colours are shown?.............................................................................................................62
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For graphics and image files two basic types are distinguished:
Vector graphics Pixel graphics
Examples: Drawings of CAD programs
Character sets type TrueType, PostScript or
OpenType
Digital photos
Files from the scanner or capture programs
Principle: Vector graphics are based on an image
description which exactly defines the objects from
which the image is made.
A circle is, for example, defined via the position of
the centre (coordinates), radius, line thickness
and colour.
A raster graphics, also pixel graphics or bitmap,
is a way of describing an image which consists of
a raster-type arrangement of pixels to which one
colour each is assigned. The main characteristics
of a raster graphics are therefore width and
height in pixels (image resolution) as well as the
colour depth.
Required memory
space:
Required memory space relatively small Depending on the resolution the required
memory space is high or very high: the files
become larger with every additionally pixel to be
stored.
Loss when scaling: Loss-free resampling (scaling) to any image sizes
possible
Resampling (scaling) to other image sizes leads
to quality loss in most cases.
Hardware performance: Since monitors are in principle based on a raster
matrix, all graphics must be resampled to
individual pixels (= rastered) to display them on
the monitor.
Depending on the complexity of the graphics very
powerful computers are needed to enable quick
processing and display.
Requirements relatively low
Typical file extensions: *.cdr (Corel Draw)
*.dwg (AutoCAD)
*.ai (Adobe Illustrator)
*.svg (Scalable Vector Graphics)
*.bmp (Bitmap)
*.gif (Compuserv GIF)
*.jpg (Joint Photographic Experts Group)
*.png (Portable Network Graphics)